Any park commissioner may be removed at the discretion of the probate judge, either upon complaint filed with such judge or upon his own motion. No such removal shall be made without giving such commissioner not less than ten days’ notice and a full opportunity to be heard in his own behalf in a public hearing. The order removing such commissioner shall state the reasons therefor and shall be entered upon the records of the probate court. In case of such removal, or in case of other vacancy in the office of commissioner, the vacancy shall be filled by the judge by appointment for the unexpired term.